CVE-2026-31798Network attack vector

MFA bypass via disabled TLS certificate verification

Published Mar 13, 2026 · Updated Mar 13, 2026

Improper certificate validation in JumpServer before 4.10.16-lts allows man-in-the-middle attackers to capture Custom SMS OTP codes. The Custom SMS client's send_sms method passes verify=False to requests, accepting a bogus HTTPS certificate while transmitting the phone number and code. Exploitation requires network-path interception and use of the Custom SMS API during a user's login, enabling MFA bypass and account access with the captured code.

CVSS severity5.0
Medium
EPSS probability0.10%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper certificate validation in JumpServer before 4.10.16-lts allows man-in-the-middle attackers to capture Custom SMS OTP codes. The Custom SMS client's send_sms method passes verify=False to requests, accepting a bogus HTTPS certificate while transmitting the phone number and code. Exploitation requires network-path interception and use of the Custom SMS API during a user's login, enabling MFA bypass and account access with the captured code.

The record

CVE
CVE-2026-31798
Published
Mar 13, 2026
Updated
Mar 13, 2026
Vendor
JumpServer
Product
JumpServer
Classifications
CWE-295, CAPEC-459, CAPEC-475, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 13, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 4.10.16-lts

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

JumpServer · JumpServerversion=< 4.10.16-lts

Published CVSS scores

5.0GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation
CAPEC-459Creating a Rogue Certification Authority Certificate
CAPEC-475Signature Spoofing by Improper Validation
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo